De-icing is defined as the removal of existing, snow, ice, frost, etc., from a surface. De-icing is very important in winter in places in the north and sometimes in really cold places in the autumn. De-icing was first used to de-ice snow and ice on roads to so that all forms of transportation can continue in extreme cold weather and also has an important impact for making the roads safer for traffic. De-icing started around the 1930’s and became more popular by the 1960´s. Ice or snow can be removed mechanically through pushing or scraping, or by heating, or by using chemicals to lower the freezing point, or by a combination of these methods.
There are many chemicals that are used to de-ice surfaces. Sodium chloride (salt) is used the most for de-icing, because it isn’t expensive and always is available in big quantities. It is spread on the icy roads by specially designed snowplows or dump trucks, with sand and gravel. The salt works by dissolving into the rain or sleet on roads and lowering the freezing point, thereby melting the ice and snow or even preventing it from forming. Since salt water freezes at -18 degrees Celsius it is pointless when the temperature goes down below this level. Getting rid of ice has many benefits, but sometimes if you have too many chemicals it can have a bad effect on the environment. Salt water also has a strong tendency to break down objects. It rusts the steel used in most vehicles.
“Deicing - Wikipedia, the free encyclopedia." Wikipedia, the free encyclopedia. N.p., n.d. Web. 8 Jan. 2011. <http://en.wikipedia.org/wiki/Deicing>.
Everywhere across the U.S during the winter, cities put tons of salt and other deicing materials on roads, streets, motorways, and airport runways. The melting and snow, ice, and chemicals run...
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